// Copyright 2016 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"flag"
	"os"

	"github.com/juju/errors"
	log "github.com/sirupsen/logrus"
)

func main() {
	cfg := NewConfig()
	err := cfg.Parse(os.Args[1:])
	switch errors.Cause(err) {
	case nil:
	case flag.ErrHelp:
		os.Exit(0)
	default:
		log.Errorf("parse cmd flags err %s\n", err)
		os.Exit(2)
	}

	table := newTable()
	err = parseTableSQL(table, cfg.DDLCfg.TableSQL)
	if err != nil {
		log.Fatal(err)
	}

	err = parseIndexSQL(table, cfg.DDLCfg.IndexSQL)
	if err != nil {
		log.Fatal(err)
	}

	dbs, err := createDBs(cfg.DBCfg, cfg.SysCfg.WorkerCount)
	if err != nil {
		log.Fatal(err)
	}
	defer closeDBs(dbs)

	if len(cfg.StatsCfg.Path) > 0 {
		statsInfo, err1 := loadStats(table.tblInfo, cfg.StatsCfg.Path)
		if err1 != nil {
			log.Fatal(err1)
		}
		for _, idxInfo := range table.tblInfo.Indices {
			offset := idxInfo.Columns[0].Offset
			if hist, ok := statsInfo.Indices[idxInfo.ID]; ok && len(hist.Buckets) > 0 {
				table.columns[offset].hist = &histogram{
					Histogram: hist.Histogram,
					index:     hist.Info,
				}
			}
		}
		for i, colInfo := range table.tblInfo.Columns {
			if hist, ok := statsInfo.Columns[colInfo.ID]; ok && table.columns[i].hist == nil && len(hist.Buckets) > 0 {
				table.columns[i].hist = &histogram{
					Histogram: hist.Histogram,
				}
			}
		}
	}

	err = execSQL(dbs[0], cfg.DDLCfg.TableSQL)
	if err != nil {
		log.Fatal(err)
	}

	err = execSQL(dbs[0], cfg.DDLCfg.IndexSQL)
	if err != nil {
		log.Fatal(err)
	}

	doProcess(table, dbs, cfg.SysCfg.JobCount, cfg.SysCfg.WorkerCount, cfg.SysCfg.Batch)
}
